Chemistry

Chemistry

1. Atomic Structure

   • The nucleus is tiny compared to the atom as a whole:
     • the radius of an atom is about 0.1 nm (1 × 10-10 m)
     • the radius of a nucleus (1 × 10-14 m) is less than \frac{1}{10,000} of the radius of an atom
   • Subatomic Partcles
     • The nuclei of all atoms contain subatomic particles called protons. The nuclei of most atoms also contain neutrons.
     • The masses of subatomic particles are very tiny. Instead of writing their actual masses in kilograms, we often use their relative masses. The relative mass of a proton is 1, and a particle with a relative mass smaller than 1 has less mass.
     • The mass of an electron is very small compared to a proton or a neutron. Since the nucleus contains protons and neutrons, most of the mass of an atom is concentrated in its nucleus
     • Protons and electrons have electrical charges that are equal and opposite.

2. Bonding

   • intermolecular bonding
     • There are several types of bonding inside molecules (intramolecular bonds) and between molecules (intermolecular bonds).